Wireless powered electrochromic windows

ABSTRACT

Electrochromic windows powered by wireless power transmission are described, particularly, the combination of low-defectivity, highly-reliable solid state electrochromic windows with wireless power transmission. Wireless power transmission networks which incorporate electrochromic windows are described.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 14/962,975, filed on Dec. 8, 2015 and titled“WIRELESS POWERED ELECTROCHROMIC WINDOWS,” which is a continuation ofU.S. patent application Ser. No. 14/735,016 (Issued as U.S. Pat. No.9,664,976), filed on Jun. 9, 2015 and titled “WIRELESS POWEREDELECTROCHROMIC WINDOWS,” which is a continuation application of U.S.patent application Ser. No. 12/971,576 (Issued as U.S. Pat. No.9,081,246), filed on Dec. 17, 2010 and titled “WIRELESS POWEREDELECTROCHROMIC WINDOWS,” which is a non-provisional application of andclaims priority to U.S. Provisional Application Ser. No. 61/289,319,filed on Dec. 22, 2009 and titled “WIRELESS POWERED ELECTROCHROMICWINDOWS;” all of which are hereby incorporated by reference in theirentirety and for all purposes.

FIELD OF THE INVENTION

The invention relates generally to the field of electrochromic (EC)devices coupled with wireless power transmission technology. Morespecifically the invention relates to EC windows powered by wirelesspower transmission technology.

BACKGROUND

Electrochromism is a phenomenon in which a material exhibits areversible electrochemically-mediated change in an optical property whenplaced in a different electronic state, typically by being subjected toa voltage change. The optical property is typically one or more ofcolor, transmittance, absorbance, and reflectance. One well known ECmaterial, for example, is tungsten oxide (WO₃). Tungsten oxide is acathodic EC material in which a coloration transition, transparent toblue, occurs by electrochemical reduction. While electrochromism wasdiscovered in the 1960's, EC devices and apparatus and systemscontaining EC devices have not begun to realize their full commercialpotential.

Electrochromic materials may be incorporated into, for example, windows.One drawback of conventional EC windows is that the power used, althoughsmall in amount, requires a hard wired connection to a power source of abuilding. This creates problems when builders are installing, forexample, a large number of windows in an office building. Having to dealwith hard wiring required for windows is just another impediment that abuilder must deal with in the long list of items necessary to build amodern structure. Also, although EC windows offer an elegant solution inthe management of heat zones in a modern building, for example, whencontrolled by an automated heat and/or energy management system, ECwindows that require hard wired power sources create impediments tointegration into automated energy management systems. Thus theadditional installation costs and risks associated with wires will slowdown the adoption of EC windows in new construction and may preventretrofit applications in many cases because retrofit requires additionalinstallation of wiring infrastructure for the new EC windows.

SUMMARY OF INVENTION

Electrochromic devices, particularly EC windows, powered by wirelesspower transmission are described. The combination of low-defectivity,highly-reliable EC windows with wireless power transmission is an aspectof the invention.

Scalable EC window technology that integrates wireless powertransmission technology to create a wirelessly-powered EC window isdescribed. Such technology may optionally include environmental sensors,wireless control and/or in some aspects photovoltaic power. Theinvention enables full benefits of EC window technology to be realizedat national level savings of quads of energy and hundreds of tons ofcarbon annually. New construction will benefit greatly from wirelesslypowered EC windows, and there is particular advantage in retrofitapplications, where installing wires for replacement windows isproblematic.

One embodiment is an EC device powered by wireless power transmission.In one embodiment, the EC device is an EC window. Wireless powertransmission is utilized to provide power to one or more EC device's inan EC window. Wireless power can be used to directly power an EC devicein the window or, in an alternative embodiment, charge an internalbattery which powers the EC transitions and/or EC states of the ECdevice(s) in the window. In one embodiment, wireless power transmissionis received by a receiver that powers more than one EC window. Wirelesspower can also be used to power other active devices which are part of,or directly support, the EC window: for example, motion sensors, lightsensors, heat sensors, moisture sensors, wireless communication sensorsand the like. Wireless communication technology can also be used tocontrol the wirelessly powered EC window.

Wireless power transmission of any suitable type can be used inconjunction with EC windows. Wireless power transmission includes, forexample but not limited to, induction, resonance induction, radiofrequency power transfer, microwave power transfer and laser powertransfer. In one embodiment, power is transmitted to a receiver viaradio frequency, and the receiver converts the power into electricalcurrent utilizing polarized waves, for example circularly polarized,elliptically polarized and/or dual polarized waves, and/or variousfrequencies and vectors. In another embodiment, power is wirelesslytransferred via inductive coupling of magnetic fields. In a specificembodiment, power is wirelessly transferred via a first resonator (acoil that converts electrical energy, e.g. AC, running through the coilinto a magnetic field), which receives power from an external supplyhard wired to the first resonator, and a second resonator (a coil thatis coupled to the magnetic field and thereby produces electrical energyvia induction), which acts as the receiver by producing an electriccurrent or potential via coupling of the magnetic resonance fields ofthe first and second resonators. Although embodiments utilizing magneticinduction need not necessarily use resonance coupled magnetic fields, inthose that do, near-field resonance from localized evanescent magneticfield patterns is a relatively efficient method of wireless powertransfer.

In one embodiment, the window receiver is an RF antenna. In anotherembodiment the RF antenna converts RF power into an electrical potentialused to function the EC device. In another embodiment the receiver is asecond resonator which is resonance coupled to a first resonator,configured so that power is transmitted wirelessly from the firstresonator to the second resonator. The second resonator converts thewirelessly transferred power into electricity to power the EC window.

Typically the receiver, whether RF antenna or secondary resonance coil,is located in the frame of the EC window, e.g., near the outer seal ofthe IGU and/or somewhere in the window frame so as not to obscure theviewable area through the glass of the IGU. Thus, in particularembodiments, the receiver is of relatively small dimensions. In oneembodiment, the receiver is of sufficiently small dimensions that theuser of the window may not recognize the receiver as being part of thewindow, but rather the receiver is hidden from the view of the user.

In one embodiment, the wireless power transmission is carried out via awireless power transmission network which includes one or more powernodes for transmitting power to window receivers in particular areas.Depending on the building or need, one or more, sometimes several nodesare used to form a network of power nodes which feed power to theirrespective window receivers. In one embodiment, where radio frequency isused to transmit power and there are more than one power node, there aremore than one frequency and/or polarization vector used in the powernodes, so that different levels or types of power are transferred fromthe various nodes to windows having different power needs. In anotherembodiment, where magnetic induction is used for wireless powertransfer, there also are one or more power nodes, but in thisembodiment, the power nodes are themselves resonators. For example, inone embodiment, a first resonator, which receives power via a powersupply, is resonance coupled to a second resonator, and the secondresonator is resonance coupled to a third resonator, for example thatdelivers power to an EC window. In this way, the second resonator actsas a power node in a power transfer network from the first resonator, tothe second resonator, to the third resonator, the third resonator actingas the receiver and transmitting power to the EC window via conversionof magnetic field to electrical power.

Another aspect of the invention is a method of powering an EC device,the method including: i) generating and/or transmitting a wireless powerto a receiver, said receiver configured to convert the wireless power toelectrical energy (e.g., electrical current or potential) used to powerthe EC device; and ii) delivering the electrical energy to the ECdevice. In one embodiment, the EC device is an EC window as describedabove. In another embodiment, i) is performed via RF; in anotherembodiment, i) is performed via magnetic induction. In one embodiment,the electrical energy from the receiver is used to charge a battery,which in turn is used to power to the EC device(s) of the EC window. Inone embodiment, a single window has a wireless power receiver, and theelectrical energy created by the receiver is used to power more than oneEC window, directly and/or by charging a battery or system of batteriesassociated with the windows.

Another aspect of the invention is a wireless power transmission networkincluding: i) a wireless power transmitter configured to transmit awireless power; ii) a power node, configured to receive the wirelesspower and relay the wireless power; iii) a receiver configured toreceive the relayed wireless power and convert the wireless power to anelectrical energy; and, iv) an EC device configured to receive theelectrical energy to power a transition between optical states and/ormaintain an optical state. The electrical energy can be received by theEC device either directly or indirectly. In one embodiment, theelectrical energy is received directly from the receiver, in anotherembodiment, the electrical energy is directed from the receiver to abattery, and then to the EC device. In one embodiment, the EC device ispart of an EC window.

In certain embodiments, the EC device receives some of its electricalenergy from a wireless power source as described above and additionalelectrical energy from a photovoltaic source that may optionally beintegrated with the EC device (e.g., in or near an IGU, for example in awindow frame). Such systems may require no wiring to power the EC deviceand associated controller, sensors and the like.

These and other features and advantages will be described in furtherdetail below, with reference to the associated drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The following detailed description can be more fully understood whenconsidered in conjunction with the drawings in which:

FIG. 1 depicts EC window fabrication including a wireless powerreceiver.

FIGS. 2A-2E are schematic representations of wireless power transmissionnetworks as described herein.

DETAILED DESCRIPTION

In the broadest sense, the invention describes an EC device powered by awireless power transmission source. In more specific embodiments, ECwindows are powered by wireless power sources. Wireless powertransmission is particularly well suited for supplying EC windows,because EC windows typically function using low potentials, on the orderof a few volts to transition an EC device and/or maintain the device'soptical state. Typically, EC windows are transitioned only a few timesper day. Also, wireless power transmission can be used to charge anassociated battery, so that indirect powering of one or more EC windowsvia wireless power transmission is achieved.

Installing windows with wires entails further considerations for thearchitect and builder, and in retrofit applications wires areparticularly problematic due to the need for additional wiringinfrastructure that was not previously installed in the building. Thecombination of these advanced technologies, wireless power transmissionand EC windows, solves these problems and provides a synergy that savesenergy, as well as time and money that would be spent integrating hardwire electrical connections of EC windows.

Dynamic, EC, insulated glass units (IGU's) for commercial andresidential windows change light transmission properties in response toa small voltage, allowing control of the amount of light and heatpassing through the windows. The EC device changes between a transparent“clear or bleached” state and a darkened (light and/or heat blocking)state using small potentials and can maintain optical states with evenless power. Dynamic EC windows can filter the amount of light passingthrough the window, in one aspect providing visibility even in itsdarkened state and thus preserving visual contact with the outsideenvironment while saving energy by, for example, blocking out heatgenerating solar rays during hot weather or keeping valuable heat in abuilding due to their insulating properties during cold weather.

One example of such dynamic windows are low-defectivity, highly-reliableEC windows which include solid-state EC stack materials. Such allsolid-state and inorganic EC devices, methods of fabricating them, anddefectivity criterion are described in more detail in U.S. patentapplication Ser. No. 12/645,111, entitled, “Fabrication ofLow-Defectivity Electrochromic Devices,” filed on Dec. 22, 2009 andnaming Mark Kozlowski et al. as inventors; and in U.S. patentapplication Ser. No. 12/645,159, entitled, “Electrochromic Devices,”filed on Dec. 22, 2009 and naming Zhongchun Wang et al. as inventors;and in U.S. patent application Ser. Nos. 12/772,055 and 12/772,075, eachfiled on Apr. 30, 2010, and in U.S. patent application Ser. Nos.12/814,277 and 12/814,279, each filed on Jun. 11, 2010—each of the fourapplications is entitled “Electrochromic Devices,” each names ZhongchunWang et al. as inventors, each of these six patent applications isincorporated by reference herein for all purposes. One aspect of theinvention is a combination of an EC window, for example, but not limitedto, an EC window described in any of these six U.S. patent applications,powered by wireless power transmission technology. The window may bepowered directly via wireless power transmission, after conversion by areceiver to electrical energy, and/or the electrical energy may be usedto charge a battery that is used to power the window.

Wireless power transmission is the process that takes place whereelectrical energy is transmitted from a power source to an electricalload, without interconnecting wires. In the broadest sense, electricalcurrent can pass through the environment, be it air, water or solidobjects without the need for wires. But more useful (controlled) formsof wireless power transmission exist, for example transmitting power viaRF, magnetic induction, lasers or microwave energy. Wirelesstransmission finds particular use in applications where instantaneous orcontinuous energy transfer is needed, but interconnecting wires areinconvenient, problematic, hazardous, or impossible. Wireless powertransfer may be inductive, including electrodynamic induction, or basedupon other known energy transfer mediums such as radio frequency (RF),microwaves and lasers.

In some embodiments, power is transferred via RF, and transformed intoelectrical potential or current by a receiver in electricalcommunication with an EC device, particularly an EC window. Oneparticularly useful method of transferring power via RF is described inUS Patent Publication 2007/0191074, from application Ser. No. 11/699,148filed Jan. 29, 2007, entitled “Power Transmission Network and Method,”by Daniel W. Harrist, et al., which is herein incorporated by referencefor all purposes.

In other embodiments, power is transferred via magnetic induction usinga first resonator powered by an external power supply and a secondresonator which converts the magnetic field energy created by the firstresonator into power that supplies the EC device of the EC window. Oneparticularly useful method of transferring power via magnetic inductionis described in US Patent Publication 2007/0222542, from applicationSer. No. 11/481,077 filed Jul. 5, 2006, entitled “Wireless Non-radiativeEnergy Transfer,” by John Joannapoulos, et al., which is hereinincorporated by reference for all purposes. Another useful method ofcontrolling wireless inductive power is described in U.S. Pat. No.7,382,636, filed Oct. 14, 2005, entitled “System and Method for Poweringa Load,” by David Baarman, et al., which is herein incorporated byreference for all purposes. EC windows described herein can incorporatesuch methods of controlling wireless power transmission.

Certain embodiments include more than one wireless power transmissionsource, that is, the invention is not limited to embodiments where asingle wireless power transmission source is used. For example, inembodiments were a wireless power transmission network is used, onewireless power transmission method, for example RF power transmission,is used in part of the network, while another method, for example,magnetic induction, is used in another part of the network.

One aspect of the invention is an EC window powered by a wireless powertransmission source. In one embodiment, the EC window can be of anyuseful size, e.g., in automotive use, such as in a sunroof or a rearview mirror where wiring is inconvenient, for example having to passthrough a windshield of a car. In one embodiment, the EC window usesarchitectural scale glass as a substrate for the EC device of thewindow. Architectural glass is glass that is used as a buildingmaterial. Architectural glass is typically used in commercial buildings,but may also be used in residential buildings and typically, but notnecessarily, separates an indoor environment from an outdoorenvironment. Architectural glass is at least 20 inches by 20 inches, andcan be as large as about 80 inches by 80 inches. In some embodiments,the EC device is all solid state and inorganic. The window will have areceiver, for example an RF receiver or resonator, as part of a windowassembly.

FIG. 1 depicts an EC window fabrication, 100, where the window assemblyincludes a receiver, 135, for receiving wireless power transmissions,converting the transmissions to an electrical energy and powering an ECdevice of the window with the electrical energy, either directly orindirectly, for example, via powering the EC device directly or charginga battery that is used to power the EC window. An EC pane, 105, havingan EC device (not shown, but for example on surface A) and bus bars,110, which power the EC device, is matched with another glass pane, 115.During fabrication of IGU, 125, a separator, 120, is sandwiched inbetween and registered with substrates 105 and 115. IGU 125 has anassociated interior space defined by the faces of the substrates incontact with separator 120 and the surfaces of the interior perimeter ofseparator 120. Separator 120 is typically a sealing separator, that is,includes a spacer and sealing between the spacer and each substratewhere they adjoin in order to hermetically seal the interior region andthus protect the interior from moisture and the like. Typically, oncethe glass panes are sealed to the separator, secondary sealing may beapplied around the outer perimeter edges separator 120 of the IGU inorder to impart not only further sealing from the ambient, but alsofurther structural rigidity to the IGU. The IGU is supported by a frameto create a window assembly, 130. A cut out of the window frame is shownto reveal wireless power receiver 135 which includes an antennae in thisexample. Receiver 135 is proximate the IGU, in this example, inside theframe of window assembly 130. The wireless power transmission receivermay be a component of a window controller.

In one embodiment, the wireless power transmission source transmitspower via a radio frequency. In such embodiments, the EC window includesa radio frequency receiver, where the radio frequency receiverconfigured to convert the radio frequency to electrical energy (e.g., anelectrical current or potential) used to power an EC device in the ECwindow. Powering the EC device includes at least one of powering anoptical transition or an optical state of the EC device. In oneembodiment, the radio frequency receiver resides in or near the IGU ofthe EC window. For example, the receiver can be in the window frame thatsupports the IGU, in an area near the spacer that separates the glasspanes of the IGU, or both. Preferably, but not necessarily, the receiverdoes not obscure the viewable area of the IGU, for example, as depictedin FIG. 1.

In another embodiment, power is wirelessly transferred via inductivecoupling of magnetic fields. In general terms, a primary coil (thatconverts electrical energy, e.g. AC, running through the coil into amagnetic field) supplied by a power source generates a magnetic fieldand a secondary coil is coupled to the magnetic field and therebyproduces electrical energy via induction. The electrical energy producedby the secondary coil is used to power the EC device, in particularembodiments an EC device of an EC window. In a specific embodiment whereresonance coupled magnetic energy is utilized, power is wirelesslytransferred via a first resonator, which receives power from an externalsupply hard wired to the first resonator, and a second resonator, whichacts as the receiver by producing an electric current via coupling ofthe magnetic resonance fields of the first and second resonators.Although embodiments utilizing magnetic induction need not necessarilyuse resonance coupled magnetic fields, in those that do, near-fieldresonance from localized evanescent magnetic field patterns is arelatively efficient method of wireless power transfer.

In one embodiment, the receiver, whether RF antenna or resonance coil,is located proximate the IGU of the EC window, e.g., near the IGU sealor the window frame so as not to obscure the viewable area through theglass of the IGU. Thus, in particular embodiments, the receiver is ofrelatively small dimensions. “Small dimensions” means, for example, thatthe receiver occupies not more than about 5% of the viewable area of theEC window. In one embodiment, the receiver occupies none of the viewablearea of the EC window, that is, the receiver is of sufficiently smalldimensions that the user of the window may not recognize the receiver asbeing part of the window, but rather the receiver is hidden from theview of the user, e.g. housed in the frame of the window. In oneembodiment, where the receiver is housed in seal area of the IGU, theframe of the window can have one or more access ports for servicing thereceiver or the receiver can be sealed permanently in the window frame.There may also be ports and/or materials transparent to the wirelesspower transmission, so that the receiver can properly receive thewireless power transmissions without interference from the window framematerial.

In particular embodiments, there is a controller, for example amicroprocessor, that regulates the potential applied to the EC deviceand may optionally control other functions (alone or combined with othermicroprocessors) such as recharging a battery used to function thewindow, wirelessly communicating with a remote control, such as a handheld, an automated heat and/or energy management system thatcommunicates wirelessly with the window controller.

In one embodiment, the wireless power transmission is carried out via anetwork which includes one or more power nodes for transmitting power towindow receivers in particular areas. Wireless power transmissionnetworks described herein can use RF, magnetic induction or both,depending on the need. Depending on the building, one or more, sometimesseveral nodes are used to form a network of power nodes which feed powerto their respective window receivers. In one embodiment, where radiofrequency is used to transmit power and there are more than one powernode, there are more than one frequency and/or polarization vector usedin the power nodes, so that different levels or types of power aretransferred from the various nodes to windows having different powerneeds.

In one embodiment, where magnetic induction is used for wireless powertransfer, there also are one or more power nodes, but in thisembodiment, the power nodes are themselves resonators. For example, inone embodiment, a first resonator, which receives power via a powersupply, is resonance coupled to a second resonator, and the secondresonator is resonance coupled to a third resonator, for example thatdelivers power to an EC window. In this way, the second resonator actsas a power node in a power transfer network from the first resonator, tothe second resonator, to the third resonator, the third resonator actingas the receiver and transmitting power to the EC window via conversionof magnetic field to electrical power. In this way, near field magneticenergy can span longer distances in order to suit the needs of theparticular building's EC windows.

Another embodiment is a method of powering an EC device, the methodcomprising: i) generating a wireless power; ii) transmitting thewireless power to a receiver; said receiver configured to convert thewireless power to an electrical energy used to power the EC device; andiii) delivering the electrical energy (e.g., current or potential) tothe EC device and/or a battery used to power the EC device. In oneembodiment, the EC device is an EC window. In other embodiments,generating the wireless power is performed via a wireless powertransmitter that transmits power via a radio frequency and theelectrical energy is a voltage potential. In another embodiment,generating the wireless power is performed via a wireless powertransmitter that transmits power via magnetic induction, in a moreparticular embodiment, resonance coupled magnetic induction. In otherparticular embodiments, ii) and iii) are accomplished via at least oneof the wireless power transmission networks as described above. In oneparticular embodiment of the above described embodiments, the EC deviceis part of an EC pane of an EC window. In an even more particularembodiment, the EC pane is of architectural glass scale. In anotherembodiment, at least one of i), ii) and iii) are performed via wirelesscommunication. One embodiment includes using the electrical energycreated by the receiver's conversion of wireless power transmission forcharging a battery that is used to power the EC device.

FIG. 2A is a schematic representation of a wireless power transmissionnetwork, 200. The wireless power transmission network has a wirelesspower transmitter, 202, that transmits wireless power, for example viaRF power or magnetic induction as described herein, to an EC window 204.The invention is not limited to EC windows, any EC device powered bywireless power transmission is within the scope of the invention.Electrochromic window 204 is configured with a receiver that convertsthe wirelessly transmitted power to electrical energy that is used tooperate the EC device in the EC window and/or window controllers,sensors and the like. In one embodiment, the electrical energy is avoltage potential used to power the EC device's transitions and/ormaintain optical states. Typically, the EC device will have anassociated controller, e.g. a microprocessor that controls and managesthe device depending on the input. Additionally, the EC device can becontrolled and managed by an external controller which communicates withthe device via a network. The input can be manually input by a user,either directly or via wireless communication, or the input can be froman automated heat and/or energy management system of a building of whichthe EC window is a component.

The wireless power transmission network is generally defined by area,206, that is, transmission of power generally is localized to area 206,but not necessarily so. Area 206 can define an area where one or morewindows reside and where wireless power will be transmitted. Transmitter202 can be outside area 206 in some embodiments (and transmit power intothe area) or inside area 206 as depicted in FIG. 2. In one embodiment,the wireless power receiver resides proximate the IGU of the EC window.Preferably the receiver does not obstruct the view through the ECwindow. One of ordinary skill in the art would appreciate that awireless power network as described can contain a plurality of ECwindows to which power is supplied wirelessly via one or moretransmitters. Also, the electrical energy produced via the wirelesspower can be used to augment a battery supply or a photovoltaic powersupply in the EC window. In one embodiment, the photovoltaic powersupply is used to augment battery charging performed via wireless powertransmission.

FIG. 2B is a schematic representation of another wireless powertransmission network, 201. Network 201 is much like network 200 asdescribed above in relation to FIG. 2A, except that the wireless powertransmitted from transmitter 202 that is received by a receiver in ECwindow 204 is used to power not only window 204 but also windows 205.That is, the receiver in a single window is configured to convertwireless power transmissions into electrical energy in order to powermore than one EC window, either directly or via a battery or batteriesthat are charged by the receiver. In this example, a receiver associatedwith window 204 converts the wireless power transmissions intoelectrical energy and transfers the energy via wires to windows 205.This has the advantage of not relying on a receiver for each window,and, although some wiring is used, it is localized to the windowinstallation area, providing electrical communication between thewindows, rather than having to be run throughout a building. Also, sinceEC windows do not have high power requirements, this configuration ispractical.

FIG. 2C is a schematic representation of another wireless powertransmission network, 208. Network 208 is much like network 200 asdescribed above in relation to FIG. 2A, except that the wireless powertransmitted from transmitter 202 is not received directly by a receiverin EC window 204, but rather relayed via a power node 210. Power node210 can either relay the power in the same form as that which itreceived (e.g. via an RF antenna or induction coil) or be configured tochange the wireless power and transmit it to the receiver in a form moresuited to the (ultimate) requirements of window 204. In one example, thepower node receives the wireless power transmission in one form, eitherRF or magnetic induction, and transmits wireless power to window 204 inthe other of the other of the aforementioned forms. One embodiment ispower node including: a wireless power transmission receiver; configuredto receive wireless power transmissions in one or more forms and convertthe transmissions to electrical energy; and a wireless power transmitterconfigured to convert the electrical energy into wireless powertransmissions in said one or more forms. In one embodiment, the wirelesspower transmitter is configured to convert the electrical energy intothe same form of wireless power transmission than the wireless powerreceiver is configured to receive. Although the form is the same, theremay be, for example, different frequency or polarity used so that thereceiver of the power node can distinguish between the wirelesstransmissions from transmitter 202 and the transmitter of the power node210. In one embodiment, the wireless power transmitter is configured toconvert the electrical energy into a different form of wireless powertransmission than the wireless power receiver is configured to receive.

FIG. 2D is a schematic representation of another wireless powertransmission network, 212. Network 212 is much like network 208 asdescribed above in relation to FIG. 2C, except that the wireless powertransmitted from transmitter 202 is relayed via a power node 210 to aplurality of windows 204. Again, power node 210 can either relay thepower in the same form as that which it received (e.g. via an RF antennaor induction coil) or be configured to change the wireless power andtransmit it to the receiver in a form more suited to the (ultimate)requirements of windows 204. In this example, transmitter 202 is outsideof area 206. In this example, the power requirements of windows 204 arethe same, however the invention is not so limited. That is, the wirelesspower transmitted from node 210 can be of a sufficient level so as tosatisfy the power requirements of EC windows having different powerneeds, for example, where components for appropriately converting thewireless power transmissions from power node 210 to electrical energyare part of each window 204's receiver.

In one embodiment fulfilling the varying power requirements of differentwindows within a wireless power transmission network is accomplishedusing different power nodes for windows with different power needs. Thepower relayed from each node can be, for example, of different powerlevel and/or transmitted in a different way. FIG. 2E is a schematicrepresentation of one such wireless power transmission network, 214.Network 214 is much like network 212 as described above in relation toFIG. 2D, except that the wireless power transmitted from transmitter 202is relayed via two power nodes, 210 and 216. Power node 210 can eitherrelay the power in the same form as that which it received (e.g. via anRF antenna or induction coil) or be configured to change the wirelesspower and transmit it to the receiver (in window 204) in a form moresuited to the (ultimate) requirements of window 204. Power node 216relays the wireless power in a manner different than power node 210,that is power node 216 is configured to change the wireless power andtransmit it to the receiver in window 218 in a form more suited to the(ultimate) requirements of window 218. In this example, window 218 isconfigured to supply power to itself and to windows 220 through wiring.Window 218 receives wireless power transmissions from node 216 and thereceiver of window 218 converts the wireless power transmission intosufficient power to operate window 218 and windows 220. Thus, inembodiments described herein, different power nodes can receive the sameform of wireless energy, for example from a single transmitter, butrelay the wireless energy in different formats for different EC devices(via associated receivers), in this example EC windows having differentpower requirements. In this example, transmitter 202 is outside of area206. In a specific embodiment, a single wireless power transmittertransmits a wireless power and each of a plurality of EC windowsincludes a receiver specifically configured to convert the wirelesspower to an electrical energy suited for the particular needs of thatwindow. In another embodiment, each window has an equivalent receiverthat converts the wireless power into the same electrical energy, butthe electrical energy is converted to the particular needs of the windowby one or more electronic components, in communication with thereceiver, for example a rectifier, voltage converter, frequency changer,transformer, or inverter.

One embodiment is a wireless power transmission network including: i) awireless power transmitter configured to transmit a wireless power; ii)a power node, configured to receive the wireless power and relay thewireless power; iii) a receiver configured to receive the relayedwireless power and convert the wireless power to an electrical energy;and iv) an EC device configured to receive the electrical energy. In oneembodiment, the EC device is an EC window. In another embodiment thepower node comprises an RF antenna. In one embodiment, the power nodecomprises an induction coil. In another embodiment the receiver is an RFreceiver. In another embodiment, the receiver is an induction coil. Inother embodiments, the power node is configured to change the wirelesspower prior to relaying the wireless power to the EC window, dependingon the requirements of the EC window. In some embodiments, the wirelesspower network includes a plurality of power nodes wherein each powernode is configured to relay power to one or more EC windows, each of theplurality of power nodes configured to relay wireless power according tothe requirements of the EC windows comprising receivers corresponding tosaid each of the plurality of power nodes.

Although the foregoing invention has been described in some detail tofacilitate understanding, the described embodiments are to be consideredillustrative and not limiting. It will be apparent to one of ordinaryskill in the art that certain changes and modifications can be practicedwithin the scope of the appended claims.

What is claimed is:
 1. An electrochromic window configured to be poweredby a wireless power transmission source.
 2. The electrochromic window ofclaim 1, wherein the wireless power transmission source transmits powervia a radio frequency or a magnetic induction.
 3. The electrochromicwindow of claim 2, comprising a receiver, said receiver configured toconvert wireless power transmissions from the wireless powertransmission source to an electrical energy used to power anelectrochromic device in the electrochromic window.
 4. Theelectrochromic window of claim 3, wherein the electrical energy is usedto charge a battery, said battery used to power the electrochromicdevice.
 5. The electrochromic window of claim 3, wherein theelectrochromic device is solid state and inorganic.
 6. Theelectrochromic window of claim 2, wherein the wireless powertransmission source transmits power via a power transmission network. 7.The electrochromic window of claim 6, wherein the power transmissionnetwork comprises a power node for relaying power transmitted from thewireless power transmission source to the electrochromic window.
 8. Theelectrochromic window of claim 7, wherein the functions of theelectrochromic window are controlled via wireless communication.
 9. Amethod of powering an electrochromic device, the method comprising: i)generating a wireless power transmission; ii) transmitting the wirelesspower transmission to a receiver; said receiver configured to convertthe wireless power transmission into an electrical energy used to powerthe electrochromic device; and iii) delivering the electrical energy tothe electrochromic device and/or a battery used to power theelectrochromic device.
 10. The method of claim 9, wherein theelectrochromic device is part of an electrochromic window.
 11. Themethod of claim 10, wherein generating a wireless power transmission isperformed via a wireless power transmitter that uses RF or magneticinduction.
 12. The method of claim 11, wherein the electrochromic windowcomprises a wireless power receiver proximate the IGU of theelectrochromic window.
 13. The method of claim 12, wherein the wirelesspower transmitter transmits the wireless power transmission to thereceiver via a wireless power transmission network.
 14. The method ofclaim 13, wherein the wireless power transmission network comprises apower node for relaying the wireless power transmission from thewireless power transmitter to the receiver.
 15. The method of claim 10,wherein the functions of the electrochromic window are controlled viawireless communication.
 16. A wireless power transmission networkcomprising: i) a wireless power transmitter configured to transmit awireless power; ii) a power node, configured to receive the wirelesspower and relay the wireless power; iii) a receiver configured toreceive the relayed wireless power and convert the wireless power to anelectrical energy; and iv) an electrochromic device configured toreceive the electrical energy.
 17. The wireless power transmissionnetwork of claim 16, wherein the electrochromic device is part of anelectrochromic window.
 18. The wireless power transmission network ofclaim 17, wherein wireless power is transmitted via RF or via magneticinduction.
 19. The wireless power transmission network of claim 18,wherein the power node is configured to convert the wireless power,depending on the requirements of the electrochromic window, prior torelaying the wireless power to the electrochromic window; wherein theconversion comprises changing the wireless power into at least one of anelectrical energy, a different form of wireless power, a differentfrequency of wireless power and a different polarity of wireless power.20. The wireless power transmission network of claim 19, furthercomprising a plurality of power nodes wherein each power node isconfigured to relay the wireless power to one or more additionalelectrochromic windows, each of the plurality of power nodes configuredto relay the wireless power according to the requirements of theelectrochromic windows comprising receivers corresponding to said eachof the plurality of power nodes.